The requirement for pacemakers and ICDs to use intravenous catheters and transvenous leads is an impediment to very long term management as most individuals will begin to develop complications related to lead system malfunction sometime in the 5–10 year time frame, often earlier. In addition, chronic transvenous lead systems, their reimplantation and removals, can damage major cardiovascular venous systems and the tricuspid valve, as well as result in life threatening perforations of the great vessels and heart. Consequently, uses of transvenous lead systems, despite their many advantages, are not without their chronic patient management limitations in those with life expectancies of more than five years. The problem of lead complications is even greater in children where body growth can substantially alter transvenous lead function and lead to additional cardiovascular problems and revisions. Moreover, transvenous systems also increase cost and require specialized interventional rooms and equipment as well as special skill for insertion. These systems are typically implanted by cardiac electrophysiologists who have had a great deal of extra training.
Further, for mere sensing, the ability to implant a sensing device through a non-transverse/endocardial/epicardial, that is, subcutaneous, placement operation would be highly beneficial. By so doing, infections would be minimized and fluoroscopic imaging would not be required for the procedure.
Typical of the known prior art are a number of U.S. patent application Publications, specifically, Pub. Nos. US 2002/0035377, US 2002/0035379, US 2002/0035381, US 2002/0052636, and US 2002/0103510, all to Bardy et al. All of these disclosures relate to an apparatus and method for performing electrical cardioversion/defibrillation and optional pacing of the heart via a totally subcutaneous non-transvenous system.
Somewhat similarly, Pub. No. US 2003/0036778 to Ostroff et al. discloses a subcutaneous cardiac device which includes a subcutaneous electrode and a housing coupled to the subcutaneous electrode by a lead with a lead wire. The subcutaneous electrode is adapted to be implanted in a frontal region of the patient so as to overlap a portion of the patient's heart.
It was in light of the foregoing that the present invention was conceived and has now been reduced to practice.